Conventional, electrically heated garments require an inner lining. The lining hides the lead wires between heating pads and acts as a substrate to attach the heating pads. A problem with using an inner lining as a substrate is that it adds another layer of fabric between the heating panel and the user which impedes efficient transfer of heat. It also increases weight, bulk and bunching by having another layer of fabric. Additionally, liners conceal attractive comfortable shell material (e.g., fleece) that a wearer may prefer over the liner.
In conventional electrically heated garments, the lead wires are insulated and float loosely behind the internal liner layer. This means that the wires are not attached to the liner or the garment and are free to move between the liner and garment. Such movability has been known to cause durability and safety problems. Problems such as wire twisting and fatigue, stress on connections, and wire positioning, may increase wire resistance, reduce overall operating efficiency, or cause a short circuit or a break in a circuit that results in failure of the system.
What is needed is an electric heating element for garments that avoids floating wires, avoids the necessity of a liner, and produces a durable, flexible, and thermally efficient element that encapsulates the wires and becomes integrated with the shell fabric. The invention is directed to overcoming one or more of the problems and solving one or more of the needs as set forth above.